Intermodal Chassis Pool Split Billing, Ocean Port Free Time, and OSRA Compliance

Three Clocks That Must Never Be Merged

Intermodal drayage runs on at least three clocks. Demurrage is the charge tied to container use at a marine terminal beyond free time. Detention or per diem in the chassis sense is the charge for use of the chassis from an Intermodal Equipment Provider, or IEP, beyond included days. Customer detention is waiting time at a shipper or receiver. These clocks start and stop on different events, are charged by different parties, and are disputed with different evidence. When a TMS stores them as one generic accessorial, billing will pass through charges it cannot explain and absorb charges it should dispute.

Free time also differs by contract and by port. The ocean carrier service contract may allow a set number of days for the container, the chassis pool agreement may allow different days for the chassis, and the terminal may publish its own tariff. Weekends, holidays, terminal closures, and government inspection holds may or may not stop a clock depending on the governing terms. The system therefore needs a rule table by ocean carrier, IEP, port, and customer, with effective dates. A dispatcher should see days remaining today, not discover expiration when an invoice arrives 30 days later.

What Chassis Split Billing Actually Means

A chassis split occurs when the chassis used to pick up a container is not the chassis returned with that container, or when a container is grounded, flipped, or transferred between chassis during the move. A street turn, a flip at a terminal, a bare chassis reposition, and a split return can each create separate billable chassis events for different parties. Split billing in pool practice means the IEP bills the party responsible for each segment of chassis use, which is why matching motor carrier, ocean carrier, and beneficial cargo owner responsibility matters so much. If your driver picks a pool chassis, delivers, and returns the box on a different chassis after a terminal flip, the invoice may show two chassis numbers for one container move. That can be correct or an error, and only event data can tell.

Capture chassis number at every gate and at every flip. The driver mobile workflow should scan the chassis plate or enter the number with a check against the pool format, photograph the chassis and container pairing at pickup and return, and record whether the move is a live lift, drop, flip, or street turn. Office staff should not reconstruct chassis numbers from the container number later. Pools bill by chassis and by day, so the chassis event log is the payable record.

IEP Per Diem and Pool Agreements

The IEP is the Intermodal Equipment Provider responsible for offering chassis for interchange and for maintaining them in roadable condition. Pool models vary: a cooperative pool, a gray pool with multiple contributors, a proprietary ocean carrier chassis arrangement, and a direct lease fleet all bill differently. The TMS equipment record should store IEP, pool name, agreement, included days, daily rate after free days, weekend and holiday treatment, and invoice contact. Without that master, an accounts payable clerk can only check arithmetic, not entitlement.

Audit each IEP invoice line against the event log before approval. Match chassis number, out gate date and time, in gate date and time, billable days, rate, and responsible party. Flag duplicate days, days after return, days billed to your company for a segment assigned to the ocean carrier, and rates that differ from the agreement. A SQL data mining audit across a quarter of pool invoices typically finds patterns: one terminal flip code that always double bills, one chassis prefix on the wrong rate, or street turns billed to both carriers. Fix the pattern, not only the invoice.

OSRA 22 and 46 CFR 541: Invoicing Discipline

The Ocean Shipping Reform Act of 2022, or OSRA 22, strengthened Federal Maritime Commission oversight of demurrage and detention invoicing. The FMC rule at 46 CFR Part 541 sets requirements for demurrage and detention invoices, including who can be billed, the information an invoice must contain, and timeframes for issuing invoices and for disputing them. In general terms, invoices must identify the billing party, the consignee or other proper party, container and shipment identifiers, the basis for the charge, free time, rates, and dispute contact information, and charges must be issued within the rule timeframe with a defined window to seek mitigation or dispute. Carriers should confirm current regulatory text and counsel for their contracts, but the operational lesson is clear: an invoice that lacks required information or arrives late should not be paid on autopilot.

Build a dispute calendar in the TMS. Log invoice receipt date, charge period, amount, required fields present or missing, dispute deadline, and evidence packet status. Send disputes in writing with gate receipts, EDI timestamps, terminal notices, and free time calculation. Track outcomes by billing party so repeat defects become a documented pattern for negotiation or an FMC complaint. This discipline also protects your own customer invoicing: when you pass a charge through, give the customer the same clarity you demand from the ocean carrier, with container, dates, free time, and proof attached.

Port Free Time Management in Daily Dispatch

Free time is managed at breakfast, not at invoice. Each morning dispatch should see containers ranked by last free day for demurrage, chassis days used, appointment availability, customs or exam holds, and empty return instructions. A container with two days of free time but no appointment is riskier than a container with one day and a confirmed slot. The board should combine terminal data, ocean carrier holds, and driver capacity. Where terminal APIs or EDI feeds provide availability and hold status, ingest them. Where they do not, a structured manual update at fixed times is better than scattered phone notes.

Pre pull, yard storage, and split moves are tools with trade offs. Pulling a container early to your yard may stop demurrage but start chassis per diem and yard handling. Waiting may save chassis days but risk demurrage and a missed delivery. The right choice depends on which clock is more expensive and which appointment is real. Give dispatch a cost comparison on the screen: demurrage per day, chassis per day, storage per day, and extra handling. That comparison is a core TMS implementation feature for drayage, and it turns arguments into arithmetic.

• Rank by last free day - Show demurrage and chassis clocks side by side each morning.
• Holds before dispatch - Customs, exam, and ocean carrier holds checked before sending a driver.
• Appointment proof - Store confirmation numbers with the load.
• Return instructions - Empty return location confirmed before delivery completes.

EDI 214 as the Proof Layer

EDI 214 transportation carrier shipment status messages carry the timestamps that settle disputes: pickup, arrival, departure, delivery, and return events with location and time. If your 214 feed is late, rounded, or sent only at delivery, you will lose arguments that your operation actually won. Configure 214 triggers at each physical event from the driver application and ELD geofence, not from office re entry. Keep the raw outbound message and the partner acknowledgment. When a customer or ocean carrier questions a detention or per diem day, send the event timeline with gate receipts, not a narrative.

That is the value of ELD and EDI integration done carefully. GPS arrival at a terminal geofence supports the gate time, the 214 proves what you reported and when, and the gate receipt proves interchange. Three sources that agree are hard to dispute. When they disagree, investigate that terminal or driver workflow until they align. Also map status codes consistently: a departed pickup code sent at arrival teaches your customers to distrust every later message.

Billing the Customer Without Passing Through Errors

Drayage billing should show container, chassis, free days, billable days, rate source, and pass through charges separated from your drayage and detention. If the IEP billed you in error and you pass it to the customer before audit, you have converted a vendor error into a customer dispute. Sequence the work: audit IEP and ocean invoices first, dispute errors, then bill the customer only validated amounts with evidence. Where customer contracts require you to bill estimated per diem at delivery and true up later, label the estimate clearly and reconcile visibly. Shippers accept pass through charges they can trace. They reject charges described only as port fees.

Rate design should reflect chassis reality. Include included chassis days in the base drayage rate, state the daily rate beyond that, define split and flip charges, and state how street turns are credited. A carrier rate matrix optimization review can compare lanes by port, pool, and customer to show where free days are routinely exceeded and whether the cause is terminal congestion, customer unloading, or dispatch timing. Price the pattern you can prove.

Roadability, Bad Order Chassis, and Interchange

Split billing disputes sometimes start with a bad order chassis. If a driver rejects a chassis at out gate for tires, brakes, lights, or twist locks, record the defect, the time lost, and the replacement chassis. If a chassis fails en route, the roadability and maintenance responsibility conversation will need the interchange inspection record. Photographs at pickup protect the carrier from being billed for prior damage and support maintenance claims against the provider. The driver workflow should make a rejected chassis a structured event, not a phone call, so operations can show the pool how often it happens at that terminal.

Terminals differ in flip and repair process. Keep notes by location in the TMS location master: where flips occur, who authorizes them, typical wait, and which receipt proves segment end. New dispatchers learn faster from location notes tied to real moves than from a general manual. Review bad order rates monthly with safety and maintenance. A rising rate at one pool location is an operational fact worth raising with the IEP with data in hand.

Weekly Reconciliation Rhythm

Reconcile weekly in four passes. First, unmatched chassis events: out gates without returns, returns without out gates, and flips without segment closure. Second, expiring free time: containers that will breach demurrage or chassis included days in the next 72 hours. Third, uninvoiced customer charges: validated per diem and demurrage not yet billed within customer terms. Fourth, disputed vendor invoices: items inside the 46 CFR 541 or contract dispute window without an evidence packet. Assign each pass an owner and a finish time. Monthly totals should show per diem cost per move, dispute recovery rate, and pass through accuracy. Those numbers tell management whether the problem is price, process, or a specific port.

Related practice areas for this work include TMS Implementation ELD and EDI Integration SQL Data Mining. Each practice page describes scope, deliverables, and how an engagement starts with a short discovery call.

How Strong Tower Consulting Helps

Strong Tower Consulting helps carriers turn a regulatory or operational requirement into a working system inside the TMS rather than a side spreadsheet that only one person understands. The work starts with a data inventory, moves to a controlled pilot on a small set of lanes or customers, and then expands with audit reports that dispatch, safety, billing, and management can all read. Strong Tower Consulting, LLC and Exspeedite LLC are separately organized sister companies under common ownership. That separation keeps consulting advice vendor neutral and focused on the carrier operation.

To discuss your fleet, your lanes, and your current systems, call 763-244-1373 and ask for Scott Elliott. A short call is enough to map the first pilot, the data you already have, and the gaps to close before an auditor, a customer, or a port authority asks for proof.

Frequently Asked Questions